A TEENAGER who starred in the 2017 war epic Dunkirk has been arrested on suspicion of murdering missing girl Gaia Pope.

Nathan Elsey, 19, and his grandmother Rosemary Dinch, 71, were arrested after the 19-year-old went missing last Tuesday.

Gaia has not been seen in over a week.

Nathan Elsey, who appeared alongside Harry Styles in Christopher Nolan’s movie Dunkirk as an extra, was held along with is grandmother Rosemary on Monday afternoon, in connection with her disappearance.

Gaia Pope has been missing for over a week [Facebook]

Dorset Police would only confirm the ages of the two arrested, and stated they are "both known to Gaia".

Mrs Dinch and Nathan have since been released under investigation.

The last reported sighting of Gaia was at an address in Manor Gardens in Swanage, at around 4pm on November 7. She was seen on CCTV running along a pavement.

Rosemary Dinch was also arrested [BBC]

In a TV interview prior to her arrest, Rosemary Dinch spoke to the BBC – saying that Gaia had banged on her from door asking for help, the day she disappeared.

"There was a sort of help me bang, a pounding. She was upset, very upset,” she said.n“I gave her a cuddle and she responded to me – I have no idea where she is – she just seems to have disappeared."

Senior Investigating Officer Neil Devoto, of Dorset Police's Major Crime Investigation Team, said yesterday: "It has been almost a week since Gaia's last confirmed sighting and she has not been seen or heard from since.

Russell Brand pictured with Gaia at a protest [Instagram]

"We have looked through CCTV that covers the Swanage area, including transport hubs, and there is nothing to suggest she has left the area.